A device of this type is already known from EP 0 896 129 A1. This device in principle is designed as a hydraulic actuating drive which can be controlled as a function of various operating parameters of the internal combustion engine. It is arranged at the drive-side end of a camshaft mounted in the cylinder head of the internal combustion engine. It substantially comprises a drive unit, which is drive-connected to a crankshaft of the internal combustion engine, and an output unit, which is connected in a rotationally fixed manner to the camshaft of the internal combustion engine. In a specific embodiment, the device is designed as what is known as a pivot-blade adjuster. The drive unit is formed by a cylindrical hollow gear which has external toothing and a plurality of hydraulic working chambers, which are separated from one another by inner radial webs. The output unit is a blade wheel which is inserted into the hollow gear. It has a plurality of blades extending radially away from its wheel hub and dividing the working chambers in the drive unit into in each case two hydraulic pressure chambers which act against one another. Furthermore, in its wheel hub, the blade wheel which is designed as an output unit has an axial through-bore. At the same time that bore is a pressure-medium passage. The side face of the blade wheel, which faces the camshaft, is fixed in a nonpositively locking manner, in the axial and peripheral directions, to the end side of the drive-side end of the camshaft by the prestressing force of a central securing bolt. That bolt is guided through this through-bore and can be screwed into an axial threaded bore in the end side of the camshaft. In addition, that side face of the blade wheel which faces the camshaft and the end side of the camshaft specifically have complementary molded elements which are a centering opening of widened diameter in the axial through-bore in the blade wheel and a centering pin of reduced diameter on the camshaft. The molded elements of the device can also be fixed to the camshaft in the radial direction by positive locking and at the same time centering occurs. The drive unit, which is a hollow gear, is mounted rotatably, via its inner radial webs, on the wheel hub of the output unit, which is a blade wheel, and the gear is connected to the output unit in a force-transmitting manner, via the pressure chambers formed inside the device. The connection is in such a manner that when a hydraulic pressure medium is applied to the pressure chambers, the output unit undergoes relative rotation or is fixed with respect to the drive unit, and therefore the camshaft is fixed with respect to the crankshaft.
However, a drawback of this known device is that the output unit of the device sometimes has to be fixed axially with a very high prestressing force of the central securing bolt to the end side of the camshaft, dependent upon the level of torques which are introduced by the drive unit and which have to be transmitted without play to the camshaft and dependent upon the associated axial and radial forces. In practice, it has been found that this high prestressing force of the securing bolt causes extremely high clamping forces to act on the output unit. This can lead to increased mechanical load and even to deformation and/or cracks in the material on the output unit. This can cause failure or reduced durability and service life of the device.